Numerical simulation of porous structure in foam concrete on thermal insulation property

Numerical simulation of porous structure in foam concrete on thermal insulation property

The thermal insulation properties of foam concrete were investigated as a function of porosity using the parameters of effective density, the effective heat conductivity and the effective specific heat and a predictive mathematical model determined. Using the model and a foam concrete density of 580kg/m3 the theoretically calculated heat conductivity was 0.145 W/(m•K) compared with the experimental measured value by TPS of 0.142 W/(m•K). The relative error between the theoretical value and the experimental value was very low at 2.1%. The effective specific heat within the model was 967.05 J/kg•K and the experimental value was 920 J/kg•K, with a relative error of 5.1%. The insulation model was then added to a heat transferring model to calculate the temperature field of foam concrete wall during a fire incident. Finally, the temperature field of a foam concrete wall and a traditional dense concrete wall during the same fire incident were calculated and compared. Comparing the temperature field of the foam concrete wall with the traditional concrete wall, it was found that at a surface temperature in the foam concrete wall of 1039℃at 360s in the side closed to the fire, the lowest temperature in the foam concrete wall remained at 20℃, for a thickness of 7mm. In contrast at a surface temperature of traditional concrete wall was 987.2℃at 360s at the fire side wall and the lowest temperature in the traditional wall was 102.9℃ at the opposite side wall surface far away from the fire direction. As expected the data demonstrated that the use of foam concrete in wall construction adds greatly to the time for people to leave in safety.

Copyright© (2012) by Asian-Australasian Association for Composite Materials (AACM). Permanent restricted access to published version due to publisher copyright policy.